Soupe au pistou, the classic Provençal summer soup made with the freshest summer vegetables, shell beans, and pasta and finished with a dollop of basil pistou, will always carry a special place in my heart—it was the first dinner I ever ate with my French host family, on the balcony, the warm southern French sun on my back. It had never in my life occurred to me to eat soup in August, but I loved it.
My host mother Alice’s version contained little more than chunks of zucchini, potato, and tomato, a handful of fresh shell beans, short strands of spaghetti, and the pistou, pesto’s streamlined French cousin — nothing more than olive oil, salt, and basil—pounded into a rough sauce , already swirled into each serving. We ate it many times in those remaining warm weeks of late summer, always on the balcony, always made the same way. I never tired of it.
A few months later, Alice was planning the week’s menu, and she asked me if I had any requests. Of course I immediately thought of soupe au pistou. “Mais Sarah,” she said reproachfully, “c’est pas la saison pour le basil.” Um, what? As an American, I had never heard of these “food seasons” that she spoke of, and besides, I had just seen basil at Monoprix the other day. But I knew better than to argue with a Frenchwoman, and instead I settled for a ham and cheese quiche. Alas, I would not eat soupe au pistou again during my year in France.
Fast forward to last weekend and the fennel, potato, and asparagus ragout that B. made for our lunches. It was about the easiest thing to do with fresh farmers market vegetables—sweat finely chopped onion with a pinch of salt, add finely chopped fennel, diced potatoes, and sliced asparagus, and simmer in just a little chicken stock until soft. Just before serving, you stir in a mixture of cream, lemon juice, Dijon mustard, and chopped parsley. A last minute stroke of genius prompted me to swirl in some leftover sorrel sauce that I had made for pizza the night before. The whole thing tasted fresh and green, and I ate it for lunch quite happily for the next three days.
To my taste, though, it just wasn’t quite right. I knew it could be better, and the sorrel sauce had got me thinking about soupe au pistou. I wondered whether I could make a spring version while remaining true to the spirit of the original.
To begin with, I cut out the cream/lemon juice/mustard addition, and decided to use a light vegetable stock instead of the overpowering chicken broth from the ragout recipe. I kept everything seasonal, using only what I found at the farmers market: onion, fennel, baby turnips, new potatoes, asparagus—and of course, sorrel. I had bought some (fairly--from Idaho) local dried flageolet beans for my soupe au pistou (ish) and another dinner that week, and while cooking them, I realized I could use the cooking liquid for the soup. It was a brilliant idea. More flavorful than water, less busy than a stronger vegetable stock. The sorrel sauce ended up being a little more fancy than the original pistou. I wanted a little garlic bite, but it's just not ready around here yet, so instead I threw in a few bulbs of green garlic with the sorrel, as well as a handful of walnuts, a pinch of salt, and a drizzle of California olive oil. What I ended up with was spring in a bowl—earthy new potatoes, sweet fennel and turnips, grassy asparagus, plump beans, and the lemony tang of sorrel to brighten all the flavors. Local, seasonal, fresh, and tasty. I’d like to think Alice would be proud of me.
Notes: If you can’t find green garlic, just use one or two garlic cloves; the garlic taste will be a bit more pronounced, but still tasty. You can also substitute pine nuts for the walnuts, if you like.
For the Soup: 1/2 cup dried flageolet beans (cannelini are fine) 1 bay leaf 1/2 medium yellow onion, diced 2 tbs. olive oil 1/2 medium fennel bulb, finely diced 5 oz. new potatoes, scrubbed and diced 1/2 lb. fat asparagus, ends trimmed and stalks peeled, tips reserved 5 oz. baby turnips, peeled and diced 4-6 cups soaking liquid from beans or vegetable stock or even just water salt and pepper
For the Sorrel Sauce: 4-5 bulbs green garlic, white and light green parts chopped roughly 2-3 tbs. chopped walnuts large bundle sorrel leaves, soaked in water for 15-20 minutes, then thoroughly drained big pinch of salt 4-5 tbs. olive oil
Preheat the oven to 200° F.
To cook the beans, rinse them well and pick through to throw out any stones. Pour the beans into a pot and cover with water by about an inch or so. Bring to a boil, cover the pot with a tight-fitting lid and place in the oven. Cook for about an hour, then check the beans for doneness. They should be about ready. Add 1 tsp. salt to the beans, and place back in the oven, checking every 20 minutes or so until the beans are creamy and cooked through. Drain the beans, reserving the liquid for the soup. If you don't believe me that you don't need to soak the beans first, do it anyway. You'll be amazed.
Heat the olive oil on medium low in a soup pot or Dutch oven. Add the onion and a pinch of salt, and gently cook five minutes or so until soft. Add the fennel, potatoes, asparagus, and another pinch of salt, and stir to coat the vegetables in olive oil. Cook for a couple of minutes, then add the bean cooking liquid (with some broth or water if there's not quite enough), and bring to a boil. Reduce the heat to medium low and let simmer 5-7 minutes until the vegetables are softened. Add the reserved asparagus tips and the turnips and continue to simmer another 5-7 minutes, until the vegetables are cooked through.
Meanwhile, for the sorrel sauce, throw the green garlic, walnuts, and sorrel into a food processor with the big pinch of salt and whiz until everything’s well-blended. You can add the olive oil while the machine is running, but I like to scrape the paste out into a bowl and then whisk the oil in, because I’m fussy like that. I think the oil tastes bitter when it’s been added to the food processor. If I’m feeling really fussy, I will do it all with a mortar and pestle, and you could do the same. To serve, ladle the soup into bowls, and top with a dollop of sorrel sauce.
Thank you for sharing, Sarah! This is slightly late for the season, since we were slow getting it up on the site, but some of you in cooler climates may still be seeing lots of asparagus at the markets, and welcome this spring soup.